Implantable medical devices (IMDs) detect, diagnose, and deliver therapy for a variety of medical conditions in patients. IMDs include implantable pulse generators (IPGs) or implantable cardioverter-defibrillators (ICDs) that deliver electrical stimuli to tissue of a patient. ICDs typically comprise, inter alia, a control module, a capacitor, and a battery that are housed in a hermetically sealed container. When therapy is required by a patient, the control module, which includes a supply circuit, signals the battery to charge the capacitor. The capacitor then discharges electrical stimuli to tissue of a patient.
During discharge of the battery to the capacitor, battery droop may occur. Battery droop involves the battery output voltage quickly dropping to a sub-nominal voltage (e.g. 1.8 volts). Thereafter, the output voltage slowly increases or recovers to near no-load voltage potential as the capacitor becomes fully charged. It is desirable to eliminate excessive battery droop since it can disturb the operation of other circuits in the IMD.